Method and apparatus for cleaning furnace checkers and flues



Oct. 15, 194

w. J. MQNTGOMERY METHOD AND APPARATUS FOR CLEANING FURNACE CHECKERS ANDFLUES Filed Aug 20, 1945 8 Sheets-Sheet 1 Attorney:

1946. w. J. MONTGOMERY- 2,409,442

METHOD AND APPARATUS FOR CLEANiNG FURNACE CHECKERS AND IiLUES Filed m.20, 1945 s Sheets-Sheet 2 Inventor LLIAMJMoIvTGoMER M ma;

t- 1946. v ,w. J. MONTGOMERY 2,409,442

METHOD AND Armnuus FOR CLEANING FURNACE CHECKERS AND FLUES Filed Aug.20, 1945 I 8 Shuts-Sheet 3 AND FLUES Oct. 15, 1946; r w. J. MONTGOMERYMETHON AND APPARATUS FOR CLEANING FURNACE GHECKERS Filed Aug. 20, 1945 8Sheets-Sheet 4 Inventor 7 CZMONT' 6 o M E i);

I W. J. MONTGOMERY METHOD, AND APPARATUS FOR GLEANINGFURNACE CHECKERSAND FLUES Oct.15

Filed Aug 20, 1945 8 Sheets-Sheat 5 I nventar MLLjAMcI/VoN'reoMER w" 15,METHOD AND APPARATUS FOR CLEANING FURNACE CHECKERS ANDFLUES w. J.MONTGOMERY Inventor MER y,

w. J. MONTGOMERY 2,409,442 METHOD AND APPARATUS FOR CLEANING FURNACECHECKERS AND FLUES Get. 15,1946.

Filed Aug. 20, 1945 8 Sheets-Sheet 7 iii Ml I ll 1 I Inventor Mum/w CZMTQoMER Wfl/////////% Oct. 15, 1946. w. J, MONTGOMERY I 2,4095442 METHODAND APPARATUS FOR CLEANING FURNACE CHECKERS AND FLUES Filed Aug.- 20,1945 s Sheets-Sheet a' v b zventor CZMNTGOMERK M21: Ila/w Patented Oct.15, 1946 4 METHOD AND APPARATUS FOR CLEANING FURNACE CHECKERS AND FLUESWilliam J Montgomery, Warren, Ohio Application August 20, 1945, SerialNo. 611,602

17 Claims.

This invention relates to improvements in a method and apparatus forcleaning furnace checkers and flues, and has for its primary object theremoval of flue dust and debris from the checkers and flues.

Another object is to carry the flue dust and debris to the base of thefurnace stack pit or uptake and deposit it on the floor of the furnacestack pit or uptake.

Another object is to remove the flue dust and debris from the floor ofthe furnace stack pit or uptake either automatically or by hand withoutinterrupting the operation of the furnace.

The above and other objects may be attained by employing this inventionwhich embodies among its features directing a fluid blast against andthrough the furnace checkers to remove flue dust and debris, suspendingthe flue dust and debris so removed on a moving fluid blast directedtoward the base of the stack pit or uptake of the furnace, depositingthe flue dust and debris on the floor of the stack pit or uptake offurnace, isolating the flue dust and debris so deposited from the restof the stack pit or uptake so that it may be removed withoutinterrupting the operation of the furnace.

Other features embody conduits mounted atop the checkers or at anyelevation of the checkers having nozzles for directing a, blast of fluidagainst or through the checkers, conduits extending longitudinally ofthe side walls of the furnace flues and having nozzles directed in sucha manner as to suspend the flue dust and debris loosened from thecheckers on a fluid blast which moves toward the base of the stack pitor uptake of the furnace, and doors adapted to be moved into a positionto isolate the flue dust and debris which is deposited on the floor ofthe stack pit or uptake by the moving blast so that removal of the fluedust and debris from the floor of the stack pit or uptake may progresswithout interrupting the operation of the furnace.

Other features include removing the flue dust and debris from the floorof the stack pit or uptake by vacuum, and water-cooling the isolatingdoors, not only to protect them from the intense heat at the base of thestack pit or uptake, but also to reduce the temperature in the isolatedarea of the furnace stack pit or uptake to protect workmen who may enterthe isolated area for the removal of the debris by hand.

In the drawings:

Figure 1 is a horizontal sectional view through a regenerative furnaceshowing the checker chambers and flues leading to the stack,

Figure 2 is a longitudinal sectional view taken substantially on theline 2-2 of Figure 1,

Figure 3 is a horizontal sectional view taken substantially on the line3-3 of Figure 2, a

Figure 4 is a vertical sectional view taken substantially. on the line44 of Figure 2, y

Figure 5 is an enlarged sectional view taken substantially on the line5-5 of Figure 1,

Figure 6 is a vertical sectional view taken substantially on the line6-6 of Figure 5,

Figure 7 is a fragmentary enlarged horizontal sectional view through thebase of a stack and a portion of the flues leading thereto showing amodified form of isolating door arrangement,

Figure 8 is a transverse sectional view taken substantially on the line8-8 of Figure 7,

Figure 9 is a sectional view taken substantially on the line 9-9 ofFigure 7,

Figure 10 is an enlarged transverse sectional View through one of theblast conduits and its nozzle,

Figure 11 is a transverse sectional view taken substantially on the linell-|l of Figure 5.

Figure 12 is an enlarged detail sectional view taken substantially onthe line |2l 2 ofFigure 3,

Figure 13 is a fragmentary longitudinal sectional view takensubstantially on the line [3-13 of Figure 12, and

Figure 14 is an enlarged detail fragmentary sectional view through thebase of a furnace stack or uptake showing a modified form of isolatingdoor and debris-receiving pit.

Referring to the drawings in detail, a furnace designated generally 20of the regenerative type is provided with the usual hearth 2| (Fig. 2)in which the combustion of the mixed gases leaving a mixing chamber 22takes place. Leading to the mixing chamber are the usual air and gasconduits 23 and 24, respectively, which in turn communicate at theirlower ends with the usual checker chambers 25 and 26 containing walls 21of checker brick. The check chambers 25 and 26 communicate at their endsopposite the air and gas conduits 23 and 24 with flues 28 which lead toa stack 29. The furnace is provided with the usual reversing valves 30(Fig. 1) and the arrangement of the various passages for the air and gassupply is of conventional form, following that ordinarily employed inregenerative furnaces of the type to which this invention relates.

vMounted atop the checker walls 21 in respective checker chambers 25 and2-8 are blast pipes or conduits 31 provided at spaced intervals withdownwardly directed nozzles 32 which are so arranged that a blast offluid is directed against the side faces of the checker walls 25 and 26to loosen flue dust and debris and cause it to be blown downwardly intothe lines 28. These blast pipes 3| are protected from the intense heatgenerated within the checker chambers, first, by a layer of asbestos 33of not too dense a form so as to allow for expansion and contraction ofthe pipes 3| under the influence of temperature. Surrounding theexterior of the asbestos covering 33 of the pipes 3| is a loosely packedinsulating substance preferably of a finely divided nature, such asSil-o-cell 34, which in turn is held in place by an outer ceramiccylindrical shell 35 formed of a suitable material, such assilica brick,and the entireinsulated piping unitis supported atop the checker wallsby a suitable ceramic structure 36 which may take the form ofrectangular slabs, as illustrated in Figures 4 and 12.

The pipes 3| lead outwardly through'the end walls of the checkerchambers and Hand are connected to a header 3'! which'in turn isconnected through a valve 38 to a pressure supply line 39 which may beconnected to a source'of pressure supply, such as an airpressurereservoir or in other instances itmay be found desirable toconnect the pipe 39 toa source of high pressure steam. As illustratedinFigure 3, the pressure line 39 is connected througha two-way valve 43,which leads through branch pipes to the valve 38, sothat one or theother set of checker chambers onopposite sides of the furnacemayselectively be cleaned. As illustrated in'Figure 3,the pressuresupplyline39 is provided with a lead which extends into each checker'chamberon opposite sides of thefurnace and is providedwith a return bendd I sothat the fluid passing through the pipes willbe superheated before itenters the header 3'! and blast pip'es "3i. A suitable shut-off valve 42is arranged to controltheflow of fluid through the supply pipes"39 andinsome instances I find it desirable to introduce apressure-reducingvalve 43, and suitable strainers 44 according to therequirements of the; particular installation.

Builtlongitudinally along each 'flue"28 atthe junctionof itsflooriandits vertical side walls of suitable heat resisting "material, such "assilica brick, is a guardor housing 45provide'd with a vertical curb 46,which curbs cooperate to form 'a longitudinally extending wellortroughll in each suchflue. Ea0h'housing15isformed with a longitudinallyextending chamber 48 containing a suitable insulating material 49 whichsurrounds a blast pipe or conduit-5U. This blast pipe or conduit isprovided at spaced intervalswith blast nozzles 5| which are directedoutwardly and at any desired angle,through the curb 46 andissurroundedby a suitable thermal insulation 52. The nozzles 50 arepreferably placed at such an angleas tocause thefluid blast issuingtherefrom S to bedirected in'the 'generaldirection'of the stack "2950-that a'longitudinalfiow of the fluid issuing from the jet't'il willbe-toward the'stack. "These pipes 53 are connected through the medium ofrisers 53 to'the pressure supply'line39, and so arrangedas to beseparately controllable through valves 54 arranged at suitable pointsin'thensystern.

Formed-at the junction of the floor 55 and th side Walls andback wall 56and5l, respectively, of the base of the stack29 is a'curb'58 forming awell 59'intowhich the flue dust and'debris is deposited. Blast pipes 60are'embedded in the curb 58 and are provided with'nozzles El'leadingoutwardly throughthe sidewall of the curb toward the interior of thewell 59. These blast pipes 50 are connected in any suitable manner tothe pipe 39 leading from thesource of'fiuid pressureand suitable valves(not shown) are. interposed for the'purpose of regulatingthe flow offluidinto the pipes 60. Formed inthe'fioor of the stack approximatelymid-way "between the sides and ends of'the well or pit 59 is an openingB3-through which a dischargepipe 64 extends. This discharge pipe isconnected'througl'i a'riser "65 with an exhaust fan 56,'which in turn isconnected to a pipe 6'! with a suitable receptacle for :back wall 51 ofthe base of the stack to the lower end of the arch 68, which establishesconnec- 'tion=between the flue 28 and the stack 29, and

against opposite side Walls 56 of the base of the stack, are inclinedchannels 69. Welded or otherwise secured to the inner faces of the websof the channels 69 are angles 10 which extend upwardly beyond the endsof the channels, as illustrated in Figure 5, and are supported at theirextreme upper ends on suitable pedestals H. These'channels EQand angles10 form guides'for supporting a door frame 12 carrying a layer ofinsulating 'brick 13 which 'forms the door for isolating the floor '55and well or pit 59 of the stack 29 from the stack when the flue dust'anddebris'is to be removed from the base thereof. In instances where it is'desired'to provide cooling for the door T3 and'the isolated-portion ofthe stack 29, the insulating brick is provided with longitudinalpassages for the reception of cooling fluid-receiving pipes 74 which areconnected together in such fashion asto' permit the flow of coolingfluid therethrough. Carried adjacent the door 13 bythe'channels 69 aresuitable conduits '15 which are preferably embedded in a suitablesupporting material 16, and these pipes 15 are likewise connected withthe'source of cooling fluid so that additional cooling may be providedfor the isolated portion of the stack and the channels 69 furtherprotected against the intense heat from the furnace. Carried at'theupper end of the door frame 72 is an ear" to which a suitable elevatingcable 18 is attached. This cable is carried over a sheave 19 supportedin any suitable manner on a bracket and the cable 18 is connected to anysuitable type of winding drum (not shown) by means of which the doorframe 12 and the .insulatingbrick carried thereby may be lifted duringthenormal operation of the furnace.

In the modified form of .stack'floor-isolating mechanism illustrated inFigures Ho 9, inclusive, I provide adjacent'the stock'base a pit 8| andextending horizontally across the arch 88 at its lower end is a channel'82. This channel extends into the pit 8|, as. illustrated in Figure "I,and has mounted therein at spaced intervals angles 83 for a purpose tobe more fully hereinafter described. A similarchannel 84. extendshorizontallyacross the back wall 51 of thebase of the stack and into thepit 8| substantiallyon a level with the'upper end of the arch 68. Likethe channel 82, the channel 84 is provided with an angle85 for a purposeto be more fully'hereinafter described. Extending'between the channels82 and 84 are isolating doors 86 carrying at opposite ends rollers 81which ride on the'fianges of the channels and the angles tofacilitateeasy movement of the doors into open or closed position. Like the door13,'the doors 86'may alsowbe provided with suitable cooling fluid.conduits 88 for the circulation of cooling fluid therethrough.

Alternatively to the form of doors illustrated in. FiguresS to 9,inclusive, there are instances when I find it desirable to employ at thebase of the stack 29' a structure such as that illustrated in Figure 14.In such a case I provide at the base of the stacka pit 89 on the upperends of the'side walls of which I support a door 90 on suitablerollers-9| which enable the door-'90 to be withdrawn from its positionbeneath the stack so that fluedustand debriswill be deposited in the-pit89. In-order to facilitate the easy'removal of such material from thepit,'I provide a carriage 92 in the form-of a receptacle which may bereadily moved from its position beneath the lower end of the stack bymovement on rollers 83 in a horizontal direction. It will be understood,of course, that a suitable pit is arranged adjacent the pit 89 for; thereception of the carriage-92. V i

In operation, it will be understood that when a certain checker chamberor flue is 'tobe cleaned,

the proper valves are opened to direct the fluid blast from the pipes 39through the superheaters 4! to the header 3'! and thence into the pipes3| resting atop the checkers. The fluid issuing throughthe nozzles32will be' directed against the sides of the checker: and down throughchecker openings so asto loosen any flue dust and debris and direct itdownwardly into the flue 28 with which the checker chamber is connected.Simultaneously with the dislodgment of the flue dust and debris from thecheckers under the influence of the fluid blast issuing from the nozzles32 pressure is admitted through the risers 53 in the proper flue 28 soas to create a fluid blast in the wellor wells 41 of the flue passagewhich is being cleaned. Due to the angular disposition of the nozzles 5|leading from the blast pipe 50 at the bottom of the flue 28 a fluidblast will :be created which moves the flue dust and debris toward thestack 29. Rising at the stack 28 and at the end of the creation of thefluid blast, upon which the flue dust and debris have been sustained,the fluedust and debris will deposit on the floor of the stack until asufficient quantity has been, accumulated to warrant its removal.

The isolating door 12 or 86, as the case may be, is then closed so as toisolatethe area upon which the flue dust and debris havelbeen depositedfrom the rest of the stack, afterwhich the removal of the fluedust anddebris from the floor 55 of the stack may proceed,'either by hand or.automatically, by operating the exhaust fan 66 and discharging the fluedust anddebris through the ,pipes 64 and 61 to anysuitable receptacle.It

is to be noted that the isolation ,of the floorof the stack does notinterrupt the flow of heated gases through the stack, though someconstriction of the passage result. Such constriction is not serious,however, and enables the furnace to .be operated continuously withoutinterrupting production for cleaning purposes.

The flue. cleaning process may be carried on continuously with theoperation of the furnace by employing the pressure-reducing valve 43,which, while causing the fluid blast to serve somewhat as a booster tothe stack draft, at the same time so regulates the pressure of the blastas to avoid interference with the furnace operation. Under suchconditions of continuous operation, itis only. necessary periodically tomanipulate the doors 12 or 86 so as to isolate the floor of the stackfrom the rest of the stack during the time that the stack cleaning is inprogress. The operation of the structure illustrated in Figure 14 --isessentially the same as that previously described, except that the door90 operates in a horizontal rather than an inclined plane, and thecarriage 92 forms a receptacle for the reception of the flue dust anddebris, which receptacle may periodically be withdrawn from its positionbeneath the stack when the door 98 is closed so that it may 'be emptied-at leisure. Doors or dampers (not shown) may be introduced in the '1.The herein described method of cleaning furnace checkers and flues whichincludes directing a fluid blast against the checkers to dislodge finedust and debris therefrom, collecting the flue dust and debris sodislodged on the floor of the furnace stock, isolating the portion ofthe floor 0f the stack upon which the flue dust and debris is collected,and removing the flue dust and debris from the isolated area.

2. The herein described method of cleaning furnace checkers and flueswhich includes directing afluid blast against the checkers to dislodgeflue dust and debris therefrom, conveying the flue dust and debris sodislodged to the base of the furnace stack, collecting the flue dust anddebris on the floor of the furnace stack, isolating the portion of thefloor of the stack upon which the flue dust and debris is collected, andremoving the flue dust and debris from the isolated area.

'3. The herein described method of cleaning furnace checkers and flueswhich includes directing a fluid blast against the checkers to dislodgeflue dust and debris therefrom, creating a fluid blast in the furnaceflues which moves toward the stackof the furnace, conveying the fluedust and debris by said fluid blast to the base of the stack, collectingthe flue dust and debris on the floor of the stack, isolating thatportion of the floor of the stack upon which the flue dust and debris iscollected, and'removing the flue dust and debris from the isolated area.

4. The herein described method of cleaning furnace checkers and flueswhich includes directing a fluid blast against the checkers to dislodgeF flue dust and debris therefrom, collecting the flue dust and debris sodislodged on the floor of the furnace stack, isolating the portion ofthe floor of the stack upon which the flue dust and debris is collected,and extracting the flue dust and debris from the isolated area under theinfluence of vacuum.

5. The herein described method of cleaning furnace checkers and flueswhich includes directing a fluid blast against the checkers to dislodgeflue dust and debristherefrom, conveying the flue dust and debris sodislodged to the base of the furnace stack, collecting the flue dust anddebris onthe floor of the furnace stack, isolating the portion of thefloor of the stack upon which the flue dust and debris is collected, andextracting the flue dust and debris from the isolated area under theinfluence of vacuum.

6. The herein described method of cleaning furnace checkers and flueswhich includes directing a fluid blast against the checkers to dislodgeflue dust and debris therefrom, creating a fluid blast in the furnaceflues which moves toward the stack ofthe furnace, conveying the fluedust and debris by said fluid blast to the base of the stack, collectingthe flue dust and debris on the floor of the stack, isolating thatportion of the "floor of the stack upon which the flue dust and debrisis collected, and extractingthe flue dust and debris from the isolatedarea under the infiuence of vacuum.

without arresting the flow of heated gasesrfrom the unisolated' fluesand checkers. of? the :furnace,

isolating that 3 portion :of ltheffloorcof :therstack eupon'which'therflue; dust and :debris is;;collected, and removingtheflue-:dust.:and debris? fromz .the

isolated area of thecstack.

18. The herein described method -;-of :cleariing furnace checkers andlfluesnwhich 1 includes aperiodically isolating certaini'ofthezcheckerchambers and flues of afurnacexfromcother checkericha-m- :bersandfluesof ,the furnace, gdirectingia fluid 'blastxagainst, theisolatedjcheckers vandalong-the isolated =flues toward ithe :stack :ofthe-furnace, :conveying v:by the fluid'xblasti' the 1 flue ,dust and.debrisdislodged :thereby along .;the flues .toward the base of the;stack. of athe furnace, collecting the flue,dust anddebrisontthe'floorgrof the;stack, without arresting the -1 flow ofheated gases 1 fromthepunisolated fines. and checkers ofzthe-furnace, isolating .that;portion of the flooraof ,the stack ,uponwhich the .flue dustz'anddebrisis collected "and extracting theflue dust :andtdebris; fronr-theisolatediareatunder the influence of-vacuum.

.- 9. The .herein described :method "of :cleaning t'furnacecheckers andflues whichincludes directing. a fluid; blastzagainstzthecheckersxtoa-dislodge .flue dust-zand debris therefrom, collectingpthe:flue dustand fclebris; so :dislodgedrom the -.floor ;.of

the furnace. stack, isolating the portion 10f the .floor of. the;stacln.upon which:the rflue; dust:and ,debris is collected,-;decreasing the itcmperature within the isolated portionofithecstach'gand re- ;moving. the flue; dust and-debris Homing-isolatedarea.

' 10. The herein idescribed rmethodz of: cleaning furnace-checkersandlfluesiwhicn includes; peri- :.o;dicallyisolating:certairroithe-:checker chambers and flues ofabfurnacelfrom:o.ther checkerpchamrbers and ,flues of i the furnace,adirecting a ffiuid blast :againstithe,isolatedicheckers: andzzalong theisolated: fluesi-toward ttheestack :of@ the .;furnace,

collecting the flue dust and debris dislodgedvand carriedby. the fluidblast .on the floorof thegstack, without: arresting 1 the diow 10f:heatedigases from the. iunisolated flues and checkers of i the furnace--isolating-that portion ;of 2131.18 floor z of the stack upon. which,the ,fluedust;=and:-debris .istcollected, vdecreasing the temperature-:within the isolated portion of the stack,- -'and removing theziflue'rdust and debris from the isolated area.

, 11. In aisystemifor-cleaning' f urnace checkers land fluesuthecombi-nationnw-ith a furnace-Which includes checker chambers, checker-s-,"in rsaid checker chambers, a stack and fluesestablishingcommunication between the checker chambers and the .stack,-of m eans to,create vanblast "of fluid tagainstthehcheckersand alongthe fines todislodge fluedust. and debris from-the checkersand to ,acenvey it alongthe .flues to 1 the floors of the .-stack, -and meanstodsolate theportion of the ,stack in which the fine .dust and, debris, collectswhereby removal c, the flue dustand, debrisfrom tthe isolated area of.the stack may progress without interference from the/heated, gasespassing through the stack.

:12.;.In asystem" for cleaning furnace checkers an'di fluesi. thecombination with a furnace which :includes pchecker chambers, checkersin said :checker chambers, astackaand flues establishingzcommunicationrbetween the checker chambers an'dgthe stack, of, meansselectively to isolate cer- Itain checker chambers and 1flues :fromother ..chambers andxflues of the furnace, means-for creating an airblast against the checkers in the isolated checker chambers to-.dislodgefluedust and:d'ebris: therefrom,- means for creating an 1 air :currentthroughthe isolated flues upon which the flue'hdust and :debris isconveyed toward. the base of sthezstack :andby which it is collected anddeposited on the floorof the stack, and means to isolate only that partof the stack containing vthe flue dust and debris from the'remainderof.the stack-whereby thefluedust and debrismay be removed withoutinterfering with the: flow of heated gases into the-stack.

.l3..In a system for cleaning furnace checkers and. flues,thecombination with a furnacewhich .includess checker chambers, checkersin said checker chambers, a stack and'flues establishing communicationbetween the checker chambers and the stack, of meansto create a blast,of fluid against the checkers and along the fluesto dislodge flue dustand debris from the. checkersand to convey it along the flues to thefloor of the stack, means to isolatethat portion of the stack inwhichtheflue dust and debris collects,,and means to decrease the temperature inthe isolated portion of the stack.

14. In a systemfor cleaning furnace checkers and flues, the combinationwith a'furnace which includes checker chambers, checkers in said checkerchambers, a stackan'd flues establishing communication between thechecker chambers and thestack, of meansselectively to isolate certainchecker chambers and'flues of the furnace, meansfor creating an airblast against the checkers in the isolated checker chambers to dislodgeiflueidust'and debris therefrom, means for creatingantair 'currentthrough the isolatedflues :upon which thei'flue'dust anddebrisis'conveyed toward the base'of the stack and by which it iscollectedanddeposited' on the floor of the stack,

means to isolate only that part of the stack containing the "flue 'dustand; debris from the "re- "mainder of' the stack, and means to cool theisoiatedportion of the stack.

"15;'The combination with means for'dislodging and conveying fluedust-anddebrisfrom-furnace checkers and depositing said flue 'dust and'debris on'the floor -of-the stack of the furnace, 'of' a door adaptedto-partially-close the stack to isolate the-floor fromthe'remainder ofthe stack Whereby removal of the flue dust and debris canprogress-without interfering with the'operation 'of the furnace.

16.In combination with a furnace stack, a door -adapted to be moved intoa position to'isolate the l floorhof thexstack from the :balance of .the

stack,:.and: means to support the door in 1 open' or -c10sed position.

1'7..='A :doorffor: isolatingzone'part not a furnace stacki fromzanotherpart .ofxsaid stack which includesgazpain of :spaced :guidesso.positioned; near ,theibasetofithe stack that whemthe dooris closed it1ies-at such: .anangle t0-:the;;major;:axis of,:the stacktasxto allowtheireepassage :of flue ,ggases through the stack, andwmeans to' open;,or;c1ose .saidtdoor.

' WILLIAM-J.-MONTGOMERY.'

